In the past, parking meters were audited by recording their functional status and counting the coins collected in each meter vault during coin collection runs. Because meter auditing is an error-prone and labor-intensive process, it is seldom performed. When an audit is performed, it rarely includes payment information on a specific meter. In fact, most parking auditing has only information related to gross earning data of several meters in a region, measured in city blocks for example, and spanning over periods as long as several weeks. As a result, coin theft, meter malfunctions, vandalism, and regulation compliance are often poorly managed because such events cannot be detected in a timely and accurate manner. The introduction of electronically auditable parking meters has partially addressed these problems by making it possible to record payment transaction, failure modes, and device status within the meter's internal memory. This information is then directly downloaded from each parking meter using a handheld device operated by meter service personnel. Depending on a parking management personnel budget, auditing intervals can range from once a week to once every several months.
To improve man-hour efficiency related to data meter information retrieval, some electronically auditable parking meters have been equipped with short-range infrared wireless interfaces that enable data to be downloaded without opening the meter housing. However, the data collection still requires personnel to be dispatched to the field, and the opportunity cost of delayed notification of meter malfunctions continues to take a significant toll on parking revenue. A trade-off still exists between timely detection of malfunctions versus the high labor costs of frequently sending personnel into the field to detect such malfunctions.
In an attempt to address meter malfunctions, parking meters have been equipped with a radio transceiver and cell phone communication devices, where the radio transceiver sends and receives fixed range beacon signals to an adjacent transceiver-equipped parking meter. In the event the meter does not hear back from an adjacent meter, a call through the cellular network is placed from the operative meter to report a non-communicative adjacent meter. A service personnel is then dispatched to find the if one parking meter has been damaged or removed, or if that the transceiver may be malfunctioning. Equipping each parking meter with a cellular communication device is known to be expensive and requires relatively high power demands, where it is desirable to have each meter operate for extended lengths of time without battery replacement or recharge. Additionally, it is found that for this system to be viable, it is necessary to have cellular communication with all of the parking meters, where it becomes prohibitively expensive and difficult in mountainous regions. Further, because the transceiver signal is a simple beacon signal, the transceivers can only determine if there is a beacon signal coming from an adjacent transceiver, thus having very limited utility with respect to the needs of comprehensive parking meter auditing.
Accordingly, there is a need to develop real-time remote parking meter auditing that automatically and remotely audits the meters with timely detection of malfunctions to provide dramatic labor savings. Unfortunately, current wireless systems are power-hungry, expensive, do not scale well as the number of devices in the network increases, are unreliable in urban environments, or have insufficient range. As a result, despite a myriad of wireless options, no parking meter system has a fully automated remote auditing system that can operate over extended periods under very low power.